Insertible saw-tooth.



` No.' r/80,000. PATBNTBD JAN. 24, 1905.

. y0. H. FOX.

INSBRTIBLE SAW TOOTH.

APPLIOATION FILED MAR. so. 1904.

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PATENTED JAN. 24, 1905.

y 0. H. FOX. INSBRTIBLB SAW TooTH.

APPLICATION FILED MAR. 30, 1904.

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Witnesses:

@am a Attorneys UNITED STATES Patented January 24, 1905.

PATENT OFFICE.

CHURCHILL HORACE FOX, OF FREDERICTON, CANADA, ASSIGNOR OF TWO-THIRDS TOHENRY G. VENESS, OF FREDERICTON, CANADA, AND LEMUEL E. BROOKS, OFWEYMOUTH, CANADA.

INSERTIBLE SAW-TOOTH.

SPECIFICATION forming part of Letters Patent No. 780,606, dated January24, 1905.

' Application led March 30, 1904. Serial No. 200,737.

T0 all whom. it may concern,.-

Beit known that I, CHURCHILL HORACE FOX, a subject of the King of GreatBritain, residing at the city of Fredericton, county of York, in theProvince of New Brunswick, Canada, have invented certain new and usefulImprovements in Insertible Saw-Teeth; and I do hereby declare that thefollowing is a full, clear, and exact description of the invention, suchas will enable others skilled in the art to which it appertains to makeand use the same.

This invention relates to certain -new and useful improvements ininsertible saw-teeth of that class in which the points only of the teethare adapted to be renewed when worn.

AThe present invention has for its objects, among others, to provide asimple and improved form of tooth-point and means for detachably holdingit in position in the shank. I aim to effect a saving in the shank ofthe tooth, which requires to be renewed but once in a great while,whilethe tooth,the cost of which is but trifling, may be renewed as often asmay be required.

A further object is to provide a construction by which every time a newtooth is put in it renews the shank as well as the tooth, so far as thewear is concerned. Usually the wear takes place not only on the point ofthe tooth, but also at the center, and when the shank gets worn it willnot carry the dust, and therefore it becomes worthless and soon has tobe discarded. By my improved construction the shank is protected fromwear by means of a slight projection on the tooth at the point where thehead of the tooth or bit comes in contactwith the shank. This is a pointsubstantially at the center of the gullet where the greatest wear comes.

Still another object is to provide for the more secure holding of theinsertible tooth in position. To this end the tooth is formed with ahead extending in the general direction of its length and having acontracted portion to engage a correspondingly-shaped recess in theshank and a portion extending at substantially right angles to thefirst-mentioned head and having a recess to receive a head on the shankand provided with `a contracted portion, so that the tooth is braced intwo directions at substantially right angles to each other and removalthereof is impossible eX- cept transversely to the plane of the face ofthe shank. `L

Other objects and advantages of the invention will hereinafterappear,and the novel featuresthereof will be specifically defined by theappended claim.

The invention is clearly illustrated in the accompanying drawings,which, with the numerals of reference marked thereon, form a part ofthis speciiication, and in which- Figure l is a face View of my'improved tooth and its shank or gullet. Fig. 2 is an edge View thereof.Fig. 3 is a plan view looking down on Fig. 1. Fig. I is a perspectiveview ofthe shank, the tooth being removed therefrom; and Fig. 5 is aperspective view of the tooth detached from the shank.

Like numerals of reference indicate like parts in the different views.

In the drawings, 1 designates the shank or gullet, adapted to beremovably inserted in the usual recess therefor in the saw-blade, butwhich is not herein illustrated. The blade or body of the saw forms nopart of the present invention, which resides solely in the insertiblesaw-tooth and itsshank or gullet. 'Hence the illustration has beenconiined to such parts. This shank or gullet is provided with a suitablehole 2 for the reception of a suitable tool (not shown) by which it maybe turned to the proper position in itsv recess in the body of the saw.The inner edge of the shank is provided with the peripheral 'depressionvor groove 3 for a purpose well understood. The shank is formed at aboutthe midportion of its curved concave face with a recess 4., having acurved end portion 4t, and at the other end of the wall of saidrecesswith a head 5, which is rounded, as seen at 6, and somewhatcontracted,.as seen at 7, and formed also with a square sho'ulder 8,extending from the contracted portion of the head to the outer peripheryof the shank, as seen most clearly in Fig. l.

9 is the tooth. It is formed with an elongated or reinforcing portion10, terminating in a head 11, with a contact rounded portion 12 and acontracted portion 13, as seen in lFig. 1. It is also provided with therecess 14, corresponding in shape to the head 5 on the shank and withthe square shoulder or face 15, matching the square shoulder or face 8on the shank, as shown clearly in Fig. 1. At the junction of the roundedface 12 of the head 11 with the curved wall of its recess a projectingportion 16 extends beyond the line joining the curves ofthe recess 17ofthe shank and the curved wall 18 of the tooth, as will be clearlyunderstood from Fig. 1. This projection is at a point where it takes thewear from the shank, and thus the life ofthe latter is materiallylengthened. The projection 16 breaks the continuity of the curved Walls17 and 18. The tooth is insertible in its shank by a movement sidewiseor at right angles to the strain on the tooth, and the tooth cannotbecome displaced during the operation of the saw.

The advantages of the construction above outlined will be apparent tothose skilled in the art, and will be readily appreciated by thosehaving occasion to use this class of devices.

Modifications in detail may be resorted to without departing from thespirit of the invention or sacrilicing any of its advantages.

That is claimed as new is An insertible saw-tooth of the characterdescribed, comprising a shank having a recess formed thereon; anenlarged rounded portion or head formed upon the said shank and having acontracted inner portion and a shoulder or abutting surface formed uponthe said shank adjacent to said contracted portion of said head, and adetachable tooth having a recess and a shoulder or abutting surfaceformed thereon, and an elongated reinforcing member formed upon the saiddetachable tooth; the said recess, abutting surface and elongatedreinforcing member coperating with the said enlarged head, abuttingsurface and recess respectively upon the said shank to hold the tooththereon, and the said reinforcing member being provided with a thickenedlower end which is adapted to project beyond the face or edge of theshank.

In Witness whereoic l have hereunto set my hand in the presence of twowitnesses.

CHURCHILL HORACE FOX.

Witnesses:

NORMAN P. MAoLEoD, W. H. BUTLER.

